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On Thursday 22 March 2007 14:04, Robin Cornelius wrote: > Thats quite cool, I never considered that there was a simple IR filter > on the front. > > I am having some ideas for some wildlife cams. My inital thoughs are:- > > a Linksys NSLU2 loaded with debian of course running of a USB stick, a > wireless adapter and a IR modified web cam (and a hub cause now i need > 3 USB sockets). NSLU2 runs of 5v and hubs are typicaly 5v or 12v so > battery operation is also possible so a small bit of voltage > conversion hastle but not a big problem. Put in a water proof box, Add > a solar pannel and a battery for day time charging and you have a > remote system. > Interesting - I run my own converted cams, together with one of those cheap security cameras you can buy which connect to a tv card, for the exact same purpose. The main problem with a webcam IR conversion is light level. Depending on the wildlife you want to watch, some form of low level lighting is likely. IR leds work well, but you need a far few to get a decent output. To enhance the effect, I "encourage" my wildlife to visit a piece of white board in the garden, on which I place a small bowl with food in it. The white board helps to make use of the IR and you get a much better picture. Some people use those stick in the ground night time lights which charge with solar power during the day - you don't need loads of light, just enough to help pick out what is happening. Light doesn't seem to deter the majority of wildlife anyway from what I have seen. There is a guy who runs a site called beautiful britain - http://www.beautifulbritain.co.uk/ which has some interesting webcam stuff on it - bird box cams and nocturnal stuff. I did do some experimenting with diy cheap lighting for night time. Never really got very far, but a bottle of coke acts as a good filter for a torch - it blocks most of the white light but through IR the light is fine! Likewise filters created from unexposed but developed film does a good job at filtering white light (as is used in the conversion of webcams to stop the white light spectrum). Mark -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html